Intel Pentium 4 Processor on 90 nm Process Thermal and Mechanical Design Guidelines

Intel® Thermal/Mechanical Reference Design Information
R
44 Intel
®
Pentium
®
4 on 90 nm Process Thermal Design Guide
4.2 Reference Thermal Solution for the Intel
®
Pentium
®
4 Processor on 90 nm Process
The Pentium 4 processor on 90 nm process will re-use the reference thermal solution for the
Pentium 4 processor with 512-KB L2 cache on 0.13 micron process at 3 GHz and above. Note
that the ability to re-use the 3GHz and higher Pentium 4 processor with 512-KB L2 cache
on 0.13 micron process reference solution depends on the ability of a chassis to deliver a
local ambient temperature at the processor heatsink of 38 °C. Table 4 shows the predicted
thermal performance, Ψ
CA
, of the reference thermal solution with a Pentium 4 processor on 90 nm
process.
Note that there is an increase in Ψ
CA
for the same thermal solution used on different processors.
This is due to an increase in power density for the Pentium 4 processor on 90 nm process. The
high set point Ψ
CA
for the Pentium 4 processor with 512-KB L2 cache on 0.13 micron process
was 0.33 °C/W at the high fan set point.
Table 4. Intel
®
Pentium
®
4 Processor on 90 nm Process Reference Thermal Solution
Performance
Fan Set Point Fan Speed Predicted Thermal
Performance, Ψca
(Mean + 3σ)
T
A
Assumption
High 4400 RPM 0.34 °C/W T
A
= 38 °C
Low 2180 RPM 0.47 °C/W T
A
= 28 °C
4.2.1 Reference Components Overview
The reference thermal mechanical solution to support the loadline A requirement target of the
Pentium 4 processor on 90 nm process consists of the following components:
• Heatsink attach clip
• Retention mechanism
• Heatsink
• Thermal interface material
• Fan and hub assembly
• Fan attach
• Fan guard (optional, non-validated)
These components are shown in an exploded assembly view in Figure 13. The approximate
assembly mass is 370 g. Refer to Appendix C for drawings of the individual components.